Controllability in partial and uncertain environments

© 2014 IEEE.Controller synthesis is a well studied problem that attempts to automatically generate an operational behaviour model of the system-to-be that satisfies a given goal when deployed in a given domain model that behaves according to specified assumptions. A limitation of many controller synthesis techniques is that they require complete descriptions of the problem domain. This is limiting in the context of modern incremental development processes when a fully described problem domain is unavailable, undesirable or uneconomical. Previous work on Modal Transition Systems (MTS) control problems exists, however it is restricted to deterministic MTSs and deterministic Labelled Transition Systems (LTS) implementations. In this paper we study the Modal Transition System Control Problem in its full generality, allowing for nondeterministic MTSs modelling the environments behaviour and nondeterministic LTS implementations. Given an nondeterministic MTS we ask if all, none or some of the nondeterministic LTSs it describes admit an LTS controller that guarantees a given property. We show a technique that solves effectively the MTS realisability problem and it can be, in some cases, reduced to deterministic control problems. In all cases the MTS realisability problem is in same complexity class as the corresponding LTS problem

Robust degradation and enhancement of robot mission behaviour in unpredictable environments

© 2015 ACM.Temporal logic based approaches that automatically generate controllers have been shown to be useful for mission level planning of motion, surveillance and navigation, among others. These approaches critically rely on the validity of the environment models used for synthesis. Yet simplifying assumptions are inevitable to reduce complexity and provide mission-level guarantees; no plan can guarantee results in a model of a world in which everything can go wrong. In this paper, we show how our approach, which reduces reliance on a single model by introducing a stack of models, can endow systems with incremental guarantees based on increasingly strengthened assumptions, supporting graceful degradation when the environment does not behave as expected, and progressive enhancement when it does

3D DATA INTEGRATION FOR WEB BASED OPEN SOURCE WebGL INTERACTIVE VISUALISATION

Recent advances in open-source geospatial technologies in WebGIS allowed the visualization of a 3D complex environment on the web, exploiting realistic Globe reproduction of the real territorial asset. At the same time, in the field of gaming technologies, the new possibilities offered by open-source WebGL JavaScript libraries allowed the creation of Virtual Reality navigation models on the web. The integration between 3D GIS globe navigation models and VR environment navigation is a solution that offers a further level of detail in web navigation, exploiting the capabilities of web browsers in the best way. This research further contributes to this field, showing a workflow to integrate different 3D data in a VR and 3D WebGIS navigation model. The case study for this research is the new building of the University of Twente, Faculty of Geo-Information Science and Earth Observation (ITC) of Enschede (The Netherlands). This work tests the online integration of variety of 3D input data that can lead to different Levels of Details (LoD) of the buildings inside the Globe-based WebGIS platform. The developed solution works on desktop and mobile devices using the capabilities of the most common web browsers, avoiding any software installation. The result of this work is based on completely open-source solutions that offers the possibility to navigate within a 3D model, which is useful for citizens, governmental or private institutions in decision-making processes. This work represents a first step towards the ambition to generate a web Digital Twin platform to combine datasets from different sources in a unique open-source solution

Minimising makespan of discrete controllers: a qualitative approach

Qualitative controller synthesis techniques produce controllers that guarantee to achieve a given goal in the presence of an adversarial environment. However, qualitative synthesis only produces one controller out of many possible solutions and typically does not provide support for expressing preferences over other alternatives. In this paper, we thus present a formal approach to reason about preferences qualitatively, restricting attention to makespan of discrete eventbased controllers for reachability goals. Time is reasoned upon symbolically, which relieves the user from providing concrete quantitative measures. In particular, we study the scenario in which durations of individual activities are not known up-front. We first show how controllers can be symbolically and fairly compared by fixing the contingencies. Then, we present an algorithm to produce controllers that are makespan-minimising

Autotrophic vs. Heterotrophic cultivation of the marine diatom cyclotella cryptica for epa production

Recently, the marketable value of ω-3 fatty acid, particularly eicosapentaenoic acid (EPA), increased considering their health effects for human consumption. Microalgae are considered a valuable and “green” source of EPA alternative to fish oils, but considerable efforts are necessary for their exploitation at an industrial level. Due to the high operation costs of photoautotrophic microalgae cultivation, heterotrophic growth represents a promising economic solution. Marine diatoms are the major ecological producers of ω-3 fatty acids. Few species of diatoms are capable to grow in the dark using organic carbon sources. The marine diatom Cyclotella cryptica was cultivated for 14 days under photoautotrophic and heterotrophic conditions to define the effects on growth parameters, lipid production, total fatty acids and EPA content. Photoautotrophic conditions led to a total EPA production of 1.6% of dry weight, 12.2 mg L−1 culture and productivity of 0.9 mg L−1 day−1 . The heterotrophy cultures reported a total EPA production of 2.7% of dry cell weight, 18 mg L−1 culture, a productivity of 1.3 mg L−1 day−1, which are promising values in the prospective of improving culture parameters for the biotechnological exploitation of dark cultivation. C. cryptica could be a potential candidate for the heterotrophic production of EPA, also considering its robustness, capacity to resist to bacterial contaminations and plasticity of lipid metabolism

Indications for flexible fiberoptic bronchoscopy and its safety in the very elderly

Aim. To evaluate the indications and the safety of fiberoptic bronchoscopy (FOB) with bronchoalveolar lavage (BAL), protected specimen brushing (PSB), endobronchial biopsy (EBB), and transbronchial biopsy (TBB) in a population of very elderly patients. Methods. We performed a retrospective study of all adult patients, aged 50 years or older, who underwent FOB in the Bronchology Unit of the University of Parma Hospital between 1 January, 2003 and 31 April, 2005. Bronchoscopy records of 436 consecutive patients, including 191 patients, 75 yrs of age and older ("very elderly"; =>75 yrs), were reviewed. Results. Patients aged 75 years were no different with regard to gender, BMI, baseline FEV1/FVC ratio, baseline SaO2, and blood pressure. The primary indication in patients aged <75 years, was to assist in the diagnosis of a pulmonary mass of unknown aetiology (33%) and to remove secretions in the very elderly patients (31%). Indications for FOB and sampling procedures in the two groups were similar. Approximately 30% of patients in each group required supplemental oxygen during the procedure and fever occurred in 9.2% and 10.3% of patients, respectively.Hypertension and bleeding were relatively rare and did not occur more often in the very elderly. Conclusions. Indication for FOB did not vary with age and adverse events in both groups were uncommon and generally not severe

The crosstalk of melatonin and hydrogen sulfide determines photosynthetic performance by regulation of carbohydrate metabolism in wheat under heat stress

Photosynthesis is a pivotal process that determines the synthesis of carbohydrates re-quired for sustaining growth under normal or stress situation. Stress exposure reduces the photosynthetic potential owing to the excess synthesis of reactive oxygen species that disturb the proper functioning of photosynthetic apparatus. This decreased photosynthesis is associated with dis-turbances in carbohydrate metabolism resulting in reduced growth under stress. We evaluated the importance of melatonin in reducing heat stress‐induced severity in wheat (Triticum aestivum L.) plants. The plants were subjected to 25 °C (optimum temperature) or 40 °C (heat stress) for 15 days at 6 h time duration and then developed the plants for 30 days. Heat stress led to oxidative stress with increased production of thiobarbituric acid reactive substances (TBARS) and hydrogen peroxide (H2O2) content and reduced accrual of total soluble sugars, starch and carbohydrate metabolism enzymes which were reflected in reduced photosynthesis. Application of melatonin not only reduced oxidative stress through lowering TBARS and H2O2 content,augmenting the activity of antioxidative enzymes but also increased the photosynthesis in plant and carbohydrate metabolism that was needed to provide energy and carbon skeleton to the developing plant under stress. However, the increase in these parameters with melatonin was mediated via hydrogen sulfide (H2S), as the inhibition of H2S by hypotaurine (HT; H2S scavenger) reversed the ameliorative effect of melatonin. This suggests a crosstalk of melatonin and H2S in protecting heat stress‐induced photosynthetic inhibition via regulation of carbohydrate metabolism

Diagnostic factors for recurrent pregnancy loss: an expanded workup

Purpose: There is limited information on the risk factors for recurrent pregnancy loss (RPL). Methods: In this study, a patient-based approach was used to investigate the possible involvement and relative relevance of a large number of diagnostic factors in 843 women with RPL who underwent an extensive diagnostic workup including 44 diagnostic factors divided into 7 major categories. Results: The rates of abnormalities found were: (1) genital infections: 11.74%; (2) uterine anatomic defects: 23.72%; (3) endocrine disorders: 29.42%; (4) thrombophilias: 62%; (5) autoimmune abnormalities: 39.2%; (6) parental karyotype abnormalities 2.25%; (7) clinical factors: 87.78%. Six hundred and fifty-nine out of eight hundred and forty-three women (78.17%) had more than one abnormality. The mean number of pregnancy losses increased by increasing the number of the abnormalities found (r = 0.86949, P < 0.02). The factors associated with the highest mean number of pregnancy losses were cervical isthmic incompetence, anti-beta-2-glycoprotein-1 antibodies, unicornuate uterus, anti-prothrombin A antibodies, protein C deficiency, and lupus anticoagulant. The majority of the considered abnormalities had similar, non-significant prevalence between women with 2 versus ≥ 3 pregnancy losses with the exception of age ≥ 35 years and MTHFR A1298C heterozygote mutation. No difference was found between women with primary and secondary RPL stratified according to the number of abnormalities detected (Chi-square: 8.55, P = 0.07). In these women, the only factors found to be present with statistically different rates were age ≥ 35 years, cigarette smoking, and genital infection by Ureaplasma. Conclusion: A patient-based diagnostic approach in women with RPL could be clinically useful and could represent a basis for future research

Morpho-anatomical and microbiological analysis of kiwifruit roots with KVDS symptoms

Italy, one of the largest producers of kiwifruit in the world, has lost 10% of its production in recent years because of the spread of the kiwifruit vine decline syndrome (KVDS). Although the aetiology of KVDS has not been characterized, root rot symptoms are often associated with water stagnation and root asphyxia. To investigate causal factors and potential solutions to counter this syndrome, an experimental trial was undertaken in a kiwifruit orchard affected by KVDS in Latina (central Italy) in 2020. Root samples from healthy plants were collected and compared with samples taken from plants affected by KVDS. Macroscopically, the roots affected by KVDS were rotting, showing a loss of rhizodermis and cortical parenchyma. Microscopic analysis revealed damage to the root system with tissue breakdown and decomposition, flaking of the rhizodermis, cortical area with a clear loss of cell turgor, initial decay of the stele and evident detachment of the cortex from the central conducting tissues. Light microscopy, morphological and molecular analyses were carried out on the rhizodermis of roots showing decay and death symptoms. Total DNA extracted from the pure fungal colonies was amplified by PCR with ITS primers, amplicons directly sequenced, and the obtained nucleotide sequences were compared with those present in the GenBank database (NCBI) through BLAST analysis. Genomic analysis allowed the identification of three abundant fungi namely Ilyonectria vredenhoekensis, Fusarium oxysporum and Paraphaeosphaeria michotii. Further investigation is required to determine the role of these fungi in KVDS, whether they are species favoured by water stagnation and root asphyxia; their abundance and presence in other regions, orchards, and kiwifruit species; if they compromise roots functionality individually or conjunction with other microbial pathogens or abiotic factors; and if they contribute to plant death associated with KVDS

Fermentation of biodegradable organic waste by the family thermotogaceae

The abundance of organic waste generated from agro-industrial processes throughout the world has become an environmental concern that requires immediate action in order to make the global economy sustainable and circular. Great attention has been paid to convert such nutrient-rich organic waste into useful materials for sustainable agricultural practices. Instead of being an environmental hazard, biodegradable organic waste represents a promising resource for the production of high value-added products such as bioenergy, biofertilizers, and biopolymers. The ability of some hyperthermophilic bacteria, e.g., the genera Thermotoga and Pseudothermotoga, to anaerobically ferment waste with the concomitant formation of bioproducts has generated great interest in the waste management sector. These biotechnologically significant bacteria possess a complementary set of thermostable enzymes to degrade complex sugars, with high production rates of biohydrogen gas and organic molecules such as acetate and lactate. Their high growth temperatures allow not only lower contamination risks but also improve substrate solubilization. This review highlights the promises and challenges related to using Thermotoga and Pseudothermotoga spp. as sustainable systems to convert a wide range of biodegradable organic waste into high value-added products